1. Field of the Invention
The present invention relates to a light source unit of an image-reading apparatus and an image-reading apparatus with the light source unit.
2. Description of the Related Art
Conventionally, as a light source of an image-reading apparatus, a configuration in which a plurality of light-emitting elements, such as light-emitting diodes (LEDs), are arranged in a straight line along a main-scanning direction has been known (for example, refer to Japanese Laid-open Patent Publication No. 2009-277551).
When performing reduction of sizes of an image-reading apparatus to which the above-described light source is applied, since a mounting space for the light source is very small, light emitted onto a medium to be lighted cannot be fully diffused, which could lead to generation of a ripple or illuminance unevenness. When the medium is read with the image-reading apparatus in such a condition, an image ripple of a striped pattern depending on a pitch between the light-emitting elements will also be generated in the generated read image of the medium.
The present invention has been made in view of the aforementioned problems, and an object of the present invention is to provide a light source unit of an image-reading apparatus and an image-reading apparatus with the light source unit having a configuration in which a plurality of light-emitting elements are arranged in a straight line to suppress generation of a ripple in light emitted linearly onto the medium to be lighted.